Urea compound and process of making same.



UNrrED STATES PATENT OFFICE.

ADOLF ISRAEL AND RICHARD KOTHE, OF ELBERFEL'D, GERMANY, ASSIGN- ORS TOFARBENFABRIKEN OF ELBERFELD (10., OF NEW YORK, N. Y.

UREA COMPOUND AND PROCESS OF MAKING SAME.

.i-SPECIFIUATION forming part of Letters Patent No. 675,630, dated June4, 1901.

Application filed December 31, 1900. Serial No. 41,629. (No specimens.)

To all whom it 72210 7] concern:

Be it known that we, ADOLF ISRAEL and RICHARD Koran, doctors ofphilosophy,chemists, (assignors to the FARBENFABRIKEN OF ELBERFELDCOMPANY, of New York,) residing at Elberfeld, Germany, have invented anew and useful Improvement in Urea Compounds and Processes of MakingSame; and we hereby declare the following to be a clear to and exactdescription of our invention.

Our invention relates to the production of a new urea derivative ofamidonaphthol sul-.

fonic acids, being an alkaline salt of an acid having the followingformula:

The new urea derivative thus obtained may be employed for themanufacture of valuable azo dyestuffs.

In carrying out our new process practically we can proceed as follows,the parts being by weight: Twelve parts of beta -amido-alphanaphthol-beta,-sulfonic acid and twelve parts of alpha amido alpha-naphthol beta ,-sulfonic acid are dissolved in about from four hundredto four hundred and fifty parts of water under the addition of a waterysolution containing twenty-four parts of sodium carbonate, (Na GO Intothe solution thus obtained a current of gaseous phosgene (0001 is slowlyintroduced at ordinary temperature under continuous stirring. Thereaction is finished when unchanged ainidonaphthol sulfonic acid doesnot precipitate any more in a test portion on the addition of an excessof diluted hydrochloric acid, and the acid liquid thus obtained is notchanged by the addition of a small quantity of sodium nitrite.

The new urea derivative is precipitated by the addition of common salt,filtered oif, pressed, and dried.

The sodium salt of the new urea derivative represents a grayish powder,being readily soluble in water and soluble with difficulty in alcohol.From the watery solution the so dium salt is precipitated by theaddition of common salt. The barium salt is a grayish powder which isdifficultly soluble in cold and readily soluble in hot water. The corre-8 5 sponding calcium salt represents a grayish powder readily soluble inhot and difficultly soluble in cold water. These salts are prepared bythe addition of solutions of BaOl or OaCl to a Watery solution of thesodium salt of the said urea derivative. On boiling the urea derivativewith the twentyfold quan tity of hydrochloric acid of twenty per cent.it dissolves, and after boiling for some hours the urea derivative isdecomposed, and the beta -amido alpha -naphthol beta sulfonic acid andalpha -amid o-alpha -naphthol-beta sulfonic acid are regenerated.

The new urea derivative is capable of combining with one and likewisewith two molecules of diazo compounds, thus furnishing, valuable azodyestuffs.

Having now described our invention and in what manner the same is to beperformed, what we claim as new, and desire to secure by Letters Patent,is

1. The process for producing a new urea derivative of amidonaphtholsulfo'nic acids by, first, dissolving an equimolecular mixture of alpha-amido-alpha -naphthol-beta4-sulfonic acid and beta- -amido-alpha-naphthol-beta sulfonic acid in water with the addition of sodiumcarbonate; secondly, introducing into the solution thus obtained acurrent of gaseous phosgene (0001 and, finally, isolating the resultinurea derivative, substantially as hereinbefore described.

2. The herein-described new urea derivative which in the form of thefree acid has the following formula:

ADOLF ISRAEL. RICHARD KOTHE.

\Vitnesses:

OTTO KoNIG, J. A. RITTERsHAUs.

